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Quantum Communication |
Quantum information science combines two of the great scientific and
technological revolutions of the 20th century, quantum mechanics and
information theory. According to the National Science and Technology
Council’s 2008 report “A Federal Vision for Quantum Information Science”,
quantum information science will enable a range of exciting new
possibilities including: greatly improved sensors with potential impact
for mineral exploration , improved medical imaging and a revolutionary
new computational paradigm that will likely lead to the creation of
computation device capable of efficiently solving problems that cannot be
solved on a classical computer.
One of
the fundamentally important research areas involved in quantum information
science is quantum communications, which deals with the exchange of information
encoded in quantum states of matter or quantum bits (known as qubits) between
both nearby and distant quantum systems. Our Quantum Communication project
performs core research on the creation, transmission, processing and measurement
of optical qubits – the quantum states of photons, with particular attention
to application to future information technologies.
Single photons at
telecommunication wavelengths can be detected with higher efficiency with our
frequency up-conversion detector.
In the past few years, we have undertaken an intensive study of quantum key
distribution (QKD) systems for secure communications. Specifically, we demonstrated
high-speed QKD systems that generate secure keys for encryption and decryption of
information using a one-time pad cipher, and extended them into a 3-node quantum
communications network. We have demonstrated the strengths and observed the
limitations of QKD systems and networks. One such limitation is the effective
communication distance of a point-to-point QKD system, which is about 100 km.
Quantum repeaters represent a promising solution to this distance limitation. It
enables quantum information exchange between two distant quantum systems including
quantum computers. Though quantum repeaters are conceptually feasible, there are
tremendous challenges to their development. Our goal in this area is to identify
the problems, find potential solutions and evaluate their capabilities and limitations
for future quantum communication applications.
In summary, we perform research and development (R&D) in quantum communication and
related measurement areas with an emphasis on applications in information technology.
Our R&D is aimed to promote US innovation, industrial competitiveness and enhance the
nation’s security. This website shows the footprint of our R&D efforts in the past few
years.
For more information concerning this program, please contact
project leader Dr. Xiao Tang (xiao.tang@nist.gov).
Keywords: quantum communication, quantum measurement science, entangled photons, quantum
teleportation and repeaters, free space optics, quantum cryptography, photon
source/detectors.
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Technical Developments |
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Frequency Converter Enables Ultra-High Sensitivity Infrared Spectrometry:
Single photon level spectroscopy for the elusive infrared region has been demonstrated as part of ITL’s Quantum Information Program. We have developed and demonstrated a new technology to measure the very low light (-126 dBm) spectra in the near infrared (IR) region using the frequency up-conversion technology developed previously.Read more here. |
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NIST Quantum Cryptography Highlighted in New Journal of Physics:
Recent research has shown that the security of a key string of finite length can only be assured for key strings of relatively long lengths, and this understanding has underscored the importance of high-speed systems that maximize key production rates. The successful efforts at NIST in quantum information research are represented in two articles in the latest issue of the New Journal of Physics: Focus on Quantum Cryptography: Theory and Practice.Read more here. |
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NIST Design Enables More Cost
Effective Quantum Key Distribution:
ITL quantum communication research team have developed a new
configuration for quantum key distribution (QKD) systems, in which the minimum number
of single photon detectors needed is halved. The new configuration greatly simplifies
the QKD structure and therefore reduced its cost.Read more here. |
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ANTD and Security Division Colaborate
to Investigate Integrating QKD into Networks.
ITL's Advanced Networking Division and Security Division are colaborating
to investigate the problems and complexity of integrating Quantum Key Distribution (QKD)
into existing network security protocols. Exisiting security protocols rely on public
key exchange methods to distribute secure keys. When quantum computers are developed such
key exchange mechanisms will be broken. Transitioning to future technologies,
such as QKD, must be done well before such threats become reality.Read more here. |
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Record key
speed set by fiber QKD system at NIST:
A QKD system, built in ITL, produced quantum
secure keys at a rate of more than 2 million bits per second (bps)
over 1 kilometer (km) of optical fiber. This is a step toward using
conventional optical fiber to distribute quantum crypto keys in local-area
networks (LANs).Read more here. |
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Three-User active QKD network developed by
ITL researchers:
ITL researchers have developed a high speed active
three-node QKD network, in which the QKD path can be routed by optical
switches. Using this network, a QKD secured video surveillance system
has been successfully demonstrated. Read more
here.
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NIST QKD system at 1310 nm combines speed and
distance:
NIST researchers developed a quantum key distribution
system with photons being transmitted at 1310 nm, where fiber loss
is small, and after wavelength conversion, being detected at 710
nm, where single photons can be detected with good performance.
Read more here.
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Wireless QKD
demonstrated by ITL and PL researchers:
Scientists from ITL and the Physics Labarotory
tested a QKD by transmitting photons over free space between two NIST
buildings that are 730 meters apart. Read more
here. |
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High-speed electronic control board makes
NIST QKD system unique:
High-speed electronics boards for controlling
the NIST QKD system were designed for both the key sender (Alice)
and receiver (Bob). An FPGA on each board allows for complex parallel
logic that is reprogramable providing a path for revisions and enhancements.
Read
more here. |
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Low-noise frequency
up-conversion single photon detector demonstrated by
NIST:
Fiber loss is small around 1310 nm and 1550 nm.
Single photons can be detected with good performance between 600 and
900 nm. The up-conversion, technology, developed by ITL, helps to
solve this dilemma. Read more here. |
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Error-correction software:
NIST computer scientists have developed
a high-speed approach to error correction adapted from telecommunications
techniques. This makes it possible to correct bit errors rapidly without
time-consuming discussions between sender and receiver and without
wasting key bits by revealing it to a potential eavesdropper. Read more
here. |
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Early Development:
Follow the various phases of the
early development of the Quantum Information Networks project. Read more
here. |
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